Method and apparatus for utilizing radiant heat energy



Aprifl I1, 1933.

G. EGLOFF El AL METHOD AND APPARATUS FOR UTILIZING RADIANT HEAT ENERGY Filed June 21, 1928 Patented Apr. 18, 1933 UNITED sTATss PATENT OFFICE,

GUSTAV EGLO FF AND LEV A. KEKLER, OF CHICAGO, ILLINOIS, ASSIGNORS TO UNI- VERSA 'L- OIL PRODUCTS COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF SOUTH DAKOTA METHOD AND APPARATUS FOR UTILIZING 'BADIANT HEAT ENERGY Application filed June 21,

The present invention relates to improvements in distributing the application of radiant heat to heat absorbing surfaces, and deals particularly with the heating of liquids in tubular heaters, such as boilers, stills and the like.

This invention relates more specifically to the use of radiant heat reflecting surfaces in the proximity of the original source of radiantenergy to distribute the radiant heat emanating from the original sourceof radiant energy onto the main body of the tubes absorbing the heat. This invention broadly contemplates reflecting surfaces either totally or partially surrounding the tube bank.

Since the reflecting power of a surface is a function of the color of the surface and its brightness, and since the brightness diminishes for the same surfaces with increase of temperature, this invention contemplates cooling the radiant heat reflecting surfaces to maintain the surfaces at their maximum reflecting power. The fluid being heated in the main body of the tube bank, or any other auxiliary fluid, may be used as the cooling medium for the radiant heat reflecting surfaces.

In a companion application, Serial No. 287,302, filed June 21, 1928, we propose to construct the tubes in such a manner that these tubes through which the liquid is passed will thus function, in varying degrees, as radiant heat reflecting surfaces. In that application we propose to accomplish the invention by making tubes closest to the source of radiant heat energy of greater radiant heat reflecting power than the tubes further away from the source of radiant heat, and in the preferred form of the invention, the radiant heat reflecting power of the tubes progressively decreases in a direction away from the source of radiant heat energy, the heat absorbing power of such tubes becoming progressivelygreater as the heat reflecting power progressively diminishes.

The present invention contemplates the use of-heat reflecting surfaces which are not used for the heatin of liquid therein, and the concept of the invention may be used alone or in combination with the concept 1928. Serial No. 287,303.

described in said application, Serial No. 287,302, filed June 21, 1928.

The utility of the invention as well as objects and advantages thereof will be more apparent from the following description:

The single figure in the drawing is a diagrammatic vertical sectional view of a furnace equipped to carry out the present invention.

Referring more in detail to the drawing, 1

' designates a furnace provided with the heat enerating chamber 2 and'tube chamber 3.

roducts of combustion are generated in the heat generating chamber 2 through the medium of the burners diagrammatically illustrated at 4, said products of combustion passing up through the flues 5 in the bridge wall 6 into the upper portion of the tube chamber 3. The s ent products of combustion are removed t rough the flue 7, which communicates with a suitable stack (not shown).

In the upper portion of the tube chamber 3 may be disposed a metal shell 8, the surface of which is so constructed as to function as a heat reflecting means whereby radiant heat energy is reflected onto the tube bank 9. For this purpose the shell may have applied thereto a coating of material possessing high radiant heat reflecting power, or the shell 8 ma contain as manufactured ingredients WhlCh normally result in a surface having high radiant heat reflecting properties. For instance, the shell 8'may be plated with chromium, nickel chromium or the like, or may be constructed of stainless steel or ascaloy and mag be subsequently polished.

s pointed out heretofore, the upper row or rows of tubes may be so constructed as to function as heat reflecting surfaces almost entirely, the heat reflecting power of said tube surfaces progressively diminishing in a direction downward through the tube bank, while the heat absorbing power progressively increases in direct relation to the decrease of heat reflecting power.

As a feature of the present invention, heat reflecting surfaces 10, 11 and 12 may be disposed ad acent the tube bank 9 in such a manner as to reflect the radiant heat into the tube bank. It is to be understood that while we have diagrammatically illustrated the radiant heat reflecting surfaces 10, 11 and 12 as bein round and rectangular, respectively, it is toie understood that this is merely diagrammatic and these surfaces may take any desired form. These surfaces 10, 11 and 12 are preferably hollow so as to permit the passa e therethrough ofa cooling medium. It will be recalled, as we pointed out heretofore, that the heat reflectin power of a surface is directly related to its brightness or dullness, and since it is well known that heat will dull a surface, we contemplate the introduction of a cooling medium into and through the radiant heat reflecting surfaces 10, 11 and 12 to maintain these surfaces at a desired brightness.

It is to be also understood that while we have illustrated the heat reflecting surfaces 10, l1 and 12 as surrounding the tube bank 9 on three sides, that this is also merely illustrative to show the concept of the invention. The invention contemplates that the heat reflecting surfaces illustrated at 10, 11 and 12 will be disposed relative to the tube bank 9 in such a manner as to most eificiently utilize the radiant heat energy available.

The products of combustion from which the total heat (both convection heat and radiant heat) is obtained maintain the refractories of the furnace, if the'same are used in place of the element 8 at incandescent temperatures, and these refractories act as the ori inal source of radiant heat energy. In utillzing the shell 8 the radiant heat reflected by said shell from the combustion chamber 2 will act in a similar manner to a source of radiant heat energy. The portion of the radiant heat energy striking the refleeting surfaces 10, 11 and 12 will be reflected from these surfaces toward the main bank of tubes 9 sothat aside from the tubes usually exposed to the usual source of radiant heat energy, additional tubes within the tube bank will obtain reflected or reradiated radiant heat energy.

By the present invention it is possible to subject to the action of radiant heat a larger portion of a tube bank and to apply the radiant heat much more uniformly throughout a greater portion of the tube bank than is possible in other types of construction.

We claim as our invention:

1. A method of distributing the application of radiant heat to heat absorbing surfaces, which comprises maintaining an original source of radiant heat energy, disposing heat reflecting surfaces in the proximity of the original source of radiant heat energy and thus distributing the radiant heat emanating from such original source to predetermined heat absorbing surfaces through the medium of said reflecting surfaces, and cooling said 

